Orifice plate



FIG. 1 is a top view of the design for an orifice plate;

FIG. 2 is a side elevational view thereof taken along lines 2--2 of FIG. 1;

FIG. 3 is a side elevational view thereof taken along lines 3--3 of FIG. 1;

FIG. 4 is a bottom view of the orifice plate;

FIG. 5 is a side view of the orifice plate taken along lines 5--5 in FIG. 4;

FIG. 6 is a side view of the orifice plate taken along the lines 6--6 of FIG. 4; and,

FIG. 7 is an oblique top view of the orifice plate. 

The ornamental design for an orifice plate, as shown and described. 